/* scope.c
*
- * Copyright (c) 1991-2002, Larry Wall
+ * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
+ * 2000, 2001, 2002, 2003, 2004, 2005, by Larry Wall and others
*
* You may distribute under the terms of either the GNU General Public
* License or the Artistic License, as specified in the README file.
* levels..."
*/
+/* This file contains functions to manipulate several of Perl's stacks;
+ * in particular it contains code to push various types of things onto
+ * the savestack, then to pop them off and perform the correct restorative
+ * action for each one. This corresponds to the cleanup Perl does at
+ * each scope exit.
+ */
+
#include "EXTERN.h"
#define PERL_IN_SCOPE_C
#include "perl.h"
-#if defined(PERL_FLEXIBLE_EXCEPTIONS)
-void *
-Perl_default_protect(pTHX_ volatile JMPENV *pcur_env, int *excpt,
- protect_body_t body, ...)
-{
- void *ret;
- va_list args;
- va_start(args, body);
- ret = vdefault_protect(pcur_env, excpt, body, &args);
- va_end(args);
- return ret;
-}
-
-void *
-Perl_vdefault_protect(pTHX_ volatile JMPENV *pcur_env, int *excpt,
- protect_body_t body, va_list *args)
-{
- int ex;
- void *ret;
-
- JMPENV_PUSH(ex);
- if (ex)
- ret = NULL;
- else
- ret = CALL_FPTR(body)(aTHX_ *args);
- *excpt = ex;
- JMPENV_POP;
- return ret;
-}
-#endif
-
SV**
Perl_stack_grow(pTHX_ SV **sp, SV **p, int n)
{
si->si_cxix = -1;
si->si_type = PERLSI_UNDEF;
New(56, si->si_cxstack, cxitems, PERL_CONTEXT);
+ /* Without any kind of initialising PUSHSUBST()
+ * in pp_subst() will read uninitialised heap. */
+ Poison(si->si_cxstack, cxitems, PERL_CONTEXT);
return si;
}
I32
Perl_cxinc(pTHX)
{
+ IV old_max = cxstack_max;
cxstack_max = GROW(cxstack_max);
Renew(cxstack, cxstack_max + 1, PERL_CONTEXT); /* XXX should fix CXINC macro */
+ /* Without any kind of initialising deep enough recursion
+ * will end up reading uninitialised PERL_CONTEXTs. */
+ Poison(cxstack + old_max + 1, cxstack_max - old_max, PERL_CONTEXT);
return cxstack_ix + 1;
}
void
-Perl_push_return(pTHX_ OP *retop)
-{
- if (PL_retstack_ix == PL_retstack_max) {
- PL_retstack_max = GROW(PL_retstack_max);
- Renew(PL_retstack, PL_retstack_max, OP*);
- }
- PL_retstack[PL_retstack_ix++] = retop;
-}
-
-OP *
-Perl_pop_return(pTHX)
-{
- if (PL_retstack_ix > 0)
- return PL_retstack[--PL_retstack_ix];
- else
- return Nullop;
-}
-
-void
Perl_push_scope(pTHX)
{
if (PL_scopestack_ix == PL_scopestack_max) {
void
Perl_pop_scope(pTHX)
{
- I32 oldsave = PL_scopestack[--PL_scopestack_ix];
+ const I32 oldsave = PL_scopestack[--PL_scopestack_ix];
LEAVE_SCOPE(oldsave);
}
void
Perl_markstack_grow(pTHX)
{
- I32 oldmax = PL_markstack_max - PL_markstack;
- I32 newmax = GROW(oldmax);
+ const I32 oldmax = PL_markstack_max - PL_markstack;
+ const I32 newmax = GROW(oldmax);
Renew(PL_markstack, newmax, I32);
PL_markstack_ptr = PL_markstack + oldmax;
Renew(PL_savestack, PL_savestack_max, ANY);
}
+void
+Perl_savestack_grow_cnt(pTHX_ I32 need)
+{
+ PL_savestack_max = PL_savestack_ix + need;
+ Renew(PL_savestack, PL_savestack_max, ANY);
+}
+
#undef GROW
void
Perl_free_tmps(pTHX)
{
/* XXX should tmps_floor live in cxstack? */
- I32 myfloor = PL_tmps_floor;
+ const I32 myfloor = PL_tmps_floor;
while (PL_tmps_ix > myfloor) { /* clean up after last statement */
SV* sv = PL_tmps_stack[PL_tmps_ix];
PL_tmps_stack[PL_tmps_ix--] = Nullsv;
sv = *sptr = NEWSV(0,0);
if (SvTYPE(osv) >= SVt_PVMG && SvMAGIC(osv) && SvTYPE(osv) != SVt_PVGV) {
+ MAGIC *mg;
sv_upgrade(sv, SvTYPE(osv));
if (SvGMAGICAL(osv)) {
- MAGIC* mg;
- bool oldtainted = PL_tainted;
+ const bool oldtainted = PL_tainted;
mg_get(osv); /* note, can croak! */
if (PL_tainting && PL_tainted &&
(mg = mg_find(osv, PERL_MAGIC_taint))) {
PL_tainted = oldtainted;
}
SvMAGIC(sv) = SvMAGIC(osv);
+ /* if it's a special scalar or if it has no 'set' magic,
+ * propagate the SvREADONLY flag. --rgs 20030922 */
+ for (mg = SvMAGIC(sv); mg; mg = mg->mg_moremagic) {
+ if (mg->mg_type == '\0'
+ || !(mg->mg_virtual && mg->mg_virtual->svt_set))
+ {
+ SvFLAGS(sv) |= SvREADONLY(osv);
+ break;
+ }
+ }
SvFLAGS(sv) |= SvMAGICAL(osv);
/* XXX SvMAGIC() is *shared* between osv and sv. This can
* lead to coredumps when both SVs are destroyed without one
PL_localizing = 1;
SvSETMAGIC(sv);
PL_localizing = 0;
- /* If we're localizing a tied array/hash element, this new sv
- * won't actually be stored in the array/hash - so it won't get
- * reaped when the localize ends. Ensure it gets reaped by
- * mortifying it instead. DAPM */
- if (SvTIED_mg(sv, PERL_MAGIC_tiedelem))
- sv_2mortal(sv);
}
return sv;
}
SSPUSHINT(SAVEt_SHARED_PVREF);
}
+/* set the SvFLAGS specified by mask to the values in val */
+
+void
+Perl_save_set_svflags(pTHX_ SV* sv, U32 mask, U32 val)
+{
+ SSCHECK(4);
+ SSPUSHPTR(sv);
+ SSPUSHINT(mask);
+ SSPUSHINT(val);
+ SSPUSHINT(SAVEt_SET_SVFLAGS);
+}
+
void
Perl_save_gp(pTHX_ GV *gv, I32 empty)
{
- SSCHECK(6);
+ SSGROW(6);
SSPUSHIV((IV)SvLEN(gv));
SvLEN(gv) = 0; /* forget that anything was allocated here */
SSPUSHIV((IV)SvCUR(gv));
void
Perl_save_item(pTHX_ register SV *item)
{
- register SV *sv = NEWSV(0,0);
+ register SV *sv = newSVsv(item);
- sv_setsv(sv,item);
SSCHECK(3);
SSPUSHPTR(item); /* remember the pointer */
SSPUSHPTR(sv); /* remember the value */
}
void
+Perl_save_bool(pTHX_ bool *boolp)
+{
+ SSCHECK(3);
+ SSPUSHBOOL(*boolp);
+ SSPUSHPTR(boolp);
+ SSPUSHINT(SAVEt_BOOL);
+}
+
+void
Perl_save_I32(pTHX_ I32 *intp)
{
SSCHECK(3);
Perl_save_padsv(pTHX_ PADOFFSET off)
{
SSCHECK(4);
+ ASSERT_CURPAD_ACTIVE("save_padsv");
SSPUSHPTR(PL_curpad[off]);
- SSPUSHPTR(PL_curpad);
+ SSPUSHPTR(PL_comppad);
SSPUSHLONG((long)off);
SSPUSHINT(SAVEt_PADSV);
}
SV **
Perl_save_threadsv(pTHX_ PADOFFSET i)
{
-#ifdef USE_5005THREADS
- SV **svp = &THREADSV(i); /* XXX Change to save by offset */
- DEBUG_S(PerlIO_printf(Perl_debug_log, "save_threadsv %"UVuf": %p %p:%s\n",
- (UV)i, svp, *svp, SvPEEK(*svp)));
- save_svref(svp);
- return svp;
-#else
Perl_croak(aTHX_ "panic: save_threadsv called in non-threaded perl");
return 0;
-#endif /* USE_5005THREADS */
}
void
void
Perl_save_clearsv(pTHX_ SV **svp)
{
+ ASSERT_CURPAD_ACTIVE("save_clearsv");
SSCHECK(2);
SSPUSHLONG((long)(svp-PL_curpad));
SSPUSHINT(SAVEt_CLEARSV);
+ SvPADSTALE_off(*svp); /* mark lexical as active */
}
void
}
void
-Perl_save_aelem(pTHX_ AV *av, I32 idx, SV **sptr)
+Perl_save_aelem(pTHX_ const AV *av, I32 idx, SV **sptr)
{
+ SV *sv;
SSCHECK(4);
SSPUSHPTR(SvREFCNT_inc(av));
SSPUSHINT(idx);
SSPUSHPTR(SvREFCNT_inc(*sptr));
SSPUSHINT(SAVEt_AELEM);
+ /* if it gets reified later, the restore will have the wrong refcnt */
+ if (!AvREAL(av) && AvREIFY(av))
+ (void)SvREFCNT_inc(*sptr);
save_scalar_at(sptr);
+ sv = *sptr;
+ /* If we're localizing a tied array element, this new sv
+ * won't actually be stored in the array - so it won't get
+ * reaped when the localize ends. Ensure it gets reaped by
+ * mortifying it instead. DAPM */
+ if (SvTIED_mg(sv, PERL_MAGIC_tiedelem))
+ sv_2mortal(sv);
}
void
-Perl_save_helem(pTHX_ HV *hv, SV *key, SV **sptr)
+Perl_save_helem(pTHX_ const HV *hv, SV *key, SV **sptr)
{
+ SV *sv;
SSCHECK(4);
SSPUSHPTR(SvREFCNT_inc(hv));
SSPUSHPTR(SvREFCNT_inc(key));
SSPUSHPTR(SvREFCNT_inc(*sptr));
SSPUSHINT(SAVEt_HELEM);
save_scalar_at(sptr);
+ sv = *sptr;
+ /* If we're localizing a tied hash element, this new sv
+ * won't actually be stored in the hash - so it won't get
+ * reaped when the localize ends. Ensure it gets reaped by
+ * mortifying it instead. DAPM */
+ if (SvTIED_mg(sv, PERL_MAGIC_tiedelem))
+ sv_2mortal(sv);
}
void
I32
Perl_save_alloc(pTHX_ I32 size, I32 pad)
{
- register I32 start = pad + ((char*)&PL_savestack[PL_savestack_ix]
+ register const I32 start = pad + ((char*)&PL_savestack[PL_savestack_ix]
- (char*)PL_savestack);
- register I32 elems = 1 + ((size + pad - 1) / sizeof(*PL_savestack));
+ register const I32 elems = 1 + ((size + pad - 1) / sizeof(*PL_savestack));
/* SSCHECK may not be good enough */
while (PL_savestack_ix + elems + 2 > PL_savestack_max)
value = (SV*)SSPOPPTR;
gv = (GV*)SSPOPPTR;
ptr = &GvSV(gv);
- SvREFCNT_dec(gv);
+ av = (AV*)gv; /* what to refcnt_dec */
goto restore_sv;
case SAVEt_GENERIC_PVREF: /* generic pv */
str = (char*)SSPOPPTR;
case SAVEt_SVREF: /* scalar reference */
value = (SV*)SSPOPPTR;
ptr = SSPOPPTR;
+ av = Nullav; /* what to refcnt_dec */
restore_sv:
sv = *(SV**)ptr;
DEBUG_S(PerlIO_printf(Perl_debug_log,
* mg_get() in save_scalar_at() croaked */
SvMAGIC(value) = 0;
}
- SvREFCNT_dec(sv);
*(SV**)ptr = value;
+ SvREFCNT_dec(sv);
PL_localizing = 2;
SvSETMAGIC(value);
PL_localizing = 0;
SvREFCNT_dec(value);
+ if (av) /* actually an av, hv or gv */
+ SvREFCNT_dec(av);
break;
case SAVEt_AV: /* array reference */
av = (AV*)SSPOPPTR;
gv = (GV*)SSPOPPTR;
if (GvAV(gv)) {
- AV *goner = GvAV(gv);
+ AV * const goner = GvAV(gv);
SvMAGIC(av) = SvMAGIC(goner);
SvFLAGS((SV*)av) |= SvMAGICAL(goner);
SvMAGICAL_off(goner);
hv = (HV*)SSPOPPTR;
gv = (GV*)SSPOPPTR;
if (GvHV(gv)) {
- HV *goner = GvHV(gv);
+ HV * const goner = GvHV(gv);
SvMAGIC(hv) = SvMAGIC(goner);
SvFLAGS(hv) |= SvMAGICAL(goner);
SvMAGICAL_off(goner);
ptr = SSPOPPTR;
*(long*)ptr = (long)SSPOPLONG;
break;
+ case SAVEt_BOOL: /* bool reference */
+ ptr = SSPOPPTR;
+ *(bool*)ptr = (bool)SSPOPBOOL;
+ break;
case SAVEt_I32: /* I32 reference */
ptr = SSPOPPTR;
*(I32*)ptr = (I32)SSPOPINT;
break;
case SAVEt_FREEOP:
ptr = SSPOPPTR;
- if (PL_comppad)
- PL_curpad = AvARRAY(PL_comppad);
+ ASSERT_CURPAD_LEGAL("SAVEt_FREEOP"); /* XXX DAPM tmp */
op_free((OP*)ptr);
break;
case SAVEt_FREEPV:
case SAVEt_CLEARSV:
ptr = (void*)&PL_curpad[SSPOPLONG];
sv = *(SV**)ptr;
+
+ DEBUG_Xv(PerlIO_printf(Perl_debug_log,
+ "Pad 0x%"UVxf"[0x%"UVxf"] clearsv: %ld sv=0x%"UVxf"<%"IVdf"> %s\n",
+ PTR2UV(PL_comppad), PTR2UV(PL_curpad),
+ (long)((SV **)ptr-PL_curpad), PTR2UV(sv), (IV)SvREFCNT(sv),
+ (SvREFCNT(sv) <= 1 && !SvOBJECT(sv)) ? "clear" : "abandon"
+ ));
+
/* Can clear pad variable in place? */
if (SvREFCNT(sv) <= 1 && !SvOBJECT(sv)) {
/*
break;
case SVt_PVCV:
Perl_croak(aTHX_ "panic: leave_scope pad code");
- case SVt_RV:
- case SVt_IV:
- case SVt_NV:
- (void)SvOK_off(sv);
- break;
default:
- (void)SvOK_off(sv);
- (void)SvOOK_off(sv);
+ SvOK_off(sv);
break;
}
+ SvPADSTALE_on(sv); /* mark as no longer live */
}
else { /* Someone has a claim on this, so abandon it. */
- U32 padflags = SvFLAGS(sv) & (SVs_PADBUSY|SVs_PADMY|SVs_PADTMP);
+ const U32 padflags = SvFLAGS(sv) & (SVs_PADMY|SVs_PADTMP);
switch (SvTYPE(sv)) { /* Console ourselves with a new value */
case SVt_PVAV: *(SV**)ptr = (SV*)newAV(); break;
case SVt_PVHV: *(SV**)ptr = (SV*)newHV(); break;
default: *(SV**)ptr = NEWSV(0,0); break;
}
SvREFCNT_dec(sv); /* Cast current value to the winds. */
- SvFLAGS(*(SV**)ptr) |= padflags; /* preserve pad nature */
+ /* preserve pad nature, but also mark as not live
+ * for any closure capturing */
+ SvFLAGS(*(SV**)ptr) |= padflags | SVs_PADSTALE;
}
break;
case SAVEt_DELETE:
value = (SV*)SSPOPPTR;
i = SSPOPINT;
av = (AV*)SSPOPPTR;
+ if (!AvREAL(av) && AvREIFY(av)) /* undo reify guard */
+ SvREFCNT_dec(value);
ptr = av_fetch(av,i,1);
if (ptr) {
sv = *(SV**)ptr;
if (sv && sv != &PL_sv_undef) {
if (SvTIED_mg((SV*)av, PERL_MAGIC_tied))
(void)SvREFCNT_inc(sv);
- SvREFCNT_dec(av);
goto restore_sv;
}
}
hv = (HV*)SSPOPPTR;
ptr = hv_fetch_ent(hv, sv, 1, 0);
if (ptr) {
- SV *oval = HeVAL((HE*)ptr);
+ const SV * const oval = HeVAL((HE*)ptr);
if (oval && oval != &PL_sv_undef) {
ptr = &HeVAL((HE*)ptr);
if (SvTIED_mg((SV*)hv, PERL_MAGIC_tied))
(void)SvREFCNT_inc(*(SV**)ptr);
- SvREFCNT_dec(hv);
SvREFCNT_dec(sv);
+ av = (AV*)hv; /* what to refcnt_dec */
goto restore_sv;
}
}
GvHV(PL_hintgv) = NULL;
}
*(I32*)&PL_hints = (I32)SSPOPINT;
+ if (PL_hints & HINT_LOCALIZE_HH) {
+ SvREFCNT_dec((SV*)GvHV(PL_hintgv));
+ GvHV(PL_hintgv) = (HV*)SSPOPPTR;
+ }
+
break;
case SAVEt_COMPPAD:
- PL_comppad = (AV*)SSPOPPTR;
+ PL_comppad = (PAD*)SSPOPPTR;
if (PL_comppad)
PL_curpad = AvARRAY(PL_comppad);
else
break;
case SAVEt_PADSV:
{
- PADOFFSET off = (PADOFFSET)SSPOPLONG;
+ const PADOFFSET off = (PADOFFSET)SSPOPLONG;
ptr = SSPOPPTR;
if (ptr)
- ((SV**)ptr)[off] = (SV*)SSPOPPTR;
+ AvARRAY((PAD*)ptr)[off] = (SV*)SSPOPPTR;
+ }
+ break;
+ case SAVEt_SAVESWITCHSTACK:
+ {
+ dSP;
+ AV* t = (AV*)SSPOPPTR;
+ AV* f = (AV*)SSPOPPTR;
+ SWITCHSTACK(t,f);
+ PL_curstackinfo->si_stack = f;
+ }
+ break;
+ case SAVEt_SET_SVFLAGS:
+ {
+ const U32 val = (U32)SSPOPINT;
+ const U32 mask = (U32)SSPOPINT;
+ sv = (SV*)SSPOPPTR;
+ SvFLAGS(sv) &= ~mask;
+ SvFLAGS(sv) |= val;
}
break;
default:
PTR2UV(cx->blk_oldcop));
PerlIO_printf(Perl_debug_log, "BLK_OLDMARKSP = %ld\n", (long)cx->blk_oldmarksp);
PerlIO_printf(Perl_debug_log, "BLK_OLDSCOPESP = %ld\n", (long)cx->blk_oldscopesp);
- PerlIO_printf(Perl_debug_log, "BLK_OLDRETSP = %ld\n", (long)cx->blk_oldretsp);
PerlIO_printf(Perl_debug_log, "BLK_OLDPM = 0x%"UVxf"\n",
PTR2UV(cx->blk_oldpm));
PerlIO_printf(Perl_debug_log, "BLK_GIMME = %s\n", cx->blk_gimme ? "LIST" : "SCALAR");
PTR2UV(cx->blk_sub.dfoutgv));
PerlIO_printf(Perl_debug_log, "BLK_SUB.HASARGS = %d\n",
(int)cx->blk_sub.hasargs);
+ PerlIO_printf(Perl_debug_log, "BLK_SUB.RETOP = 0x%"UVxf"\n",
+ PTR2UV(cx->blk_sub.retop));
break;
case CXt_SUB:
PerlIO_printf(Perl_debug_log, "BLK_SUB.CV = 0x%"UVxf"\n",
(int)cx->blk_sub.hasargs);
PerlIO_printf(Perl_debug_log, "BLK_SUB.LVAL = %d\n",
(int)cx->blk_sub.lval);
+ PerlIO_printf(Perl_debug_log, "BLK_SUB.RETOP = 0x%"UVxf"\n",
+ PTR2UV(cx->blk_sub.retop));
break;
case CXt_EVAL:
PerlIO_printf(Perl_debug_log, "BLK_EVAL.OLD_IN_EVAL = %ld\n",
SvPVX(cx->blk_eval.old_namesv));
PerlIO_printf(Perl_debug_log, "BLK_EVAL.OLD_EVAL_ROOT = 0x%"UVxf"\n",
PTR2UV(cx->blk_eval.old_eval_root));
+ PerlIO_printf(Perl_debug_log, "BLK_EVAL.RETOP = 0x%"UVxf"\n",
+ PTR2UV(cx->blk_eval.retop));
break;
case CXt_LOOP:
}
#endif /* DEBUGGING */
}
+
+/*
+ * Local variables:
+ * c-indentation-style: bsd
+ * c-basic-offset: 4
+ * indent-tabs-mode: t
+ * End:
+ *
+ * vim: shiftwidth=4:
+*/